Simultaneous production of T helper-1-like cytokines and cytolytic activity by tumor-specific T cells in ovarian and breast cancer

Cytotoxic T-cell (CTL) cultures were generated from five ovarian cancer patients (OvCTL) and from three breast cancer patients (BrCTL). All CTL lines were T-cell receptor (TcR) αβ⁺ and predominantly CD8⁺ (73 ± 13%). These CTL lines preferentially recognized autologous tumor cells in an HLA class I-restricted, and in part HLA-A2-restricted, manner. In addition, the CTL lines recognized allogeneic HLA-A2⁺ ovarian and breast tumor cells. Specific recognition was determined by T-cell-mediated cytotoxicity as well as cytokine release. Coculture of irradiated autologous tumor cells with OvCTL induced secretion of IFN-γ, GM-CSF and TNF-α, but not IL-4, indicating a T helper-1-type response. Similar results were obtained when OvCTL and BrCTL were stimulated with histologically matched HLA-A2⁺ tumor cells. Also, BrCTL stimulated with HLA-A2⁺ but not HLA-A2^- ovarian tumor cells produced significant levels of GM-CSF and TNF-α. Finally, the Her2/neu peptide p654-662, earlier identified as a tumor antigen in both ovarian and breast cancer, induced cytotoxicity as well as the specific release of IFN-γ and TNF-α but not IL-4 by OvCTL and BrCTL. Thus, tumor-specific recognition by CTL was verified by cytotoxicity and cytokine release. The secretion of Th1-like cytokines as opposed to Th2-like cytokines suggest that therapeutically OvCTL and BrCTL could potentially enhance the endogenous immune response to tumor.